1. Field of the Invention
The present invention relates to an electronic circuit device including an electronic circuit constituted by electronic components and circuit wiring, and a heat sink structure for the electronic circuit device.
2. Description of the Related Art
A backflow prevention circuit or an ORing circuit may be provided on the output side (load side) of a power-supply device such as a DC-DC converter or an AC-DC converter in the conventional techniques (see Japanese Patent Application Laid-Open No. Hei. 8-251818 or Japanese Patent Application Laid-Open No. 2014-176242, for example). Of these, the backflow prevention circuit is used to prevent, when a secondary battery, for example, is connected as a load, the inflow (i.e., backflow) of current from the secondary battery to the power-supply device or to prevent the backflow of current from the output side to a power-supply device due to unequal outputs from a plurality of power-supply devices connected in parallel.
The ORing circuit is used, when a plurality of power-supply devices connected in parallel are used, to achieve stable power supply to a load by disconnecting a failed power-supply device from the load and to prevent the backflow of current to the power-supply device. Moreover, the provision of the ORing circuit allows for the replacement or repair of the failed power-supply device while power supply to the load is continued.
Such backflow prevention circuits and ORing circuits typically utilize the rectification of a diode in the conventional techniques. In recent years, however, mainstream backflow prevention circuits and ORing circuits perform switching between connection and disconnection of a power-supply device to and from a load by a switching element such as a metal oxide semiconductor field effect transistor (MOSFET). Since power supply from the power-supply device to the load is performed via these circuits, the use of the switching element, instead of the diode, can reduce power loss. In particular, when output power is large, such circuits are effective to use.